RCE in Sophos Firewall

CVE-2025-6704

An arbitrary file writing vulnerability in the Secure PDF eXchange (SPX) feature of Sophos Firewall versions older than 21.0 MR2 (21.0.2) can lead to pre-auth remote code execution, if a specific configuration of SPX is enabled in combination with the firewall running in High Availability (HA) mode.

Vulnerability class: Command Injection (OS Command Injection)

Published · last modified .

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.095 (95.3th percentile), scored .

Low probability of exploitation in the next 30 days, but still tracked. 95th percentile — 95.3% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2025-6704: held from 0.093 to 0.095.

EPSS over last 30 days · oldest: 0.093 · newest: 0.095 · change: +0.002

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2025-6704?
CVE-2025-6704 is a critical-severity vulnerability in Sophos Firewall, classified under OS Command Injection. CVSS score: 9.8/10. Published 2025-07-21.
How severe is CVE-2025-6704?
Critical severity. CVSS v3 base score is 9.8 out of 10.